This invention relates generally to gas turbine engine inspections and, more particularly, to a method and apparatus utilized to perform gas turbine maintenance.
Aircraft engines typically include a compressor, a combustor, and a turbine that is coupled to the compressor. Moreover, at least one known turbine engine includes an accessory gearbox having an inlet that is coupled to either the compressor or the turbine, such that rotation of gearbox inlet provides the rotational force to drive various accessory devices that may be coupled to the gearbox output.
During operation, turbine engines may suffer performance degradation and fabrication limitations due to an increase, over time, in accumulation of deposits on turbine components. Turbine components suffer an increase in their surface roughness, particularly those located in an engine operating environment, partially because they are exposed to engine combustion gases. A maintenance procedure, for example, a borescope inspection, of these components typically reveals a significant accumulation of dirt and other deposits on surfaces of the engine components.
To borescope a turbine engine, at least one known turbine engine includes a removable plug to faciliate rotating at least a portion of the turbine engine during the maintenance procedure. More specifically, at least one known turbine engine includes a plug that is removed from the accessory gearbox such that an operator can insert a tool through the an opening created by removing the plug and thus gain access to the internal gears within the gearbox. The tool is then utilized to manually rotate the gearbox and thus rotate the compressor and/or the turbine to perform the maintenance procedure.
After the maintenance procedure is completed, the tool is removed and the plug is reinstalled. However, if the plug is not properly replaced following the maintenance procedure the plug may loosen during flight resulting in low oil pressure and an engine In Flight Shut Down (IFSD).